Telnet is the lifeblood of UNIX servers connected to the Internet. UNIX is
primarily a command line driven operating system, and behaves like a faster, more
powerful, and multitasking MS-DOS. Telnet is a means to log into a UNIX server across the
Internet, as though you were sitting directly at a keyboard connected to the server
itself.
The command line, text interface to UNIX works through a tool called a shell.
The shell is what takes your commands and sends them to the operating system itself to be
carried out. The shell you will use by default on lsyf/yoa servers is BASH [Bourne-again
shell] Unix commands are notably cryptic, it has been said that Unix IS a user- friendly
operating system, it users just very choosy about who its friends are!
UNIX actually has an extremely advanced graphical interface (X-windows) that
behaves as a graphical version of telnet. What telnet can do:
- Execute files - You can run programs you've
compiled, or programs already on the server. Or test the execution of PERL scripts, or
other CGI files.
- Create/Edit files - You may use file editing
programs such as pico and vi to edit and compose files.
- Send/Receive Email - Using pine you can both
read and compose e-mail for any mail account. To login to any mail account using pine,
just telnet to your domain using the login and password for the POP account.
- Change File Permission - You may modify file
permissions using the chmod command. Further details in Chapter 2: The Unix File System.
First you must obtain a telnet client. Although there is a basic telnet.exe that
comes with Windows, it is exceedingly primitive and lacks functionality that will ease
your telnet experience. Any good shareware site will have many telnet clients listed for
Windows/Mac etc.
Logging In - Before logging in take, the time to
configure your telnet client to use the correct terminal type for the lsyf/yoa servers.
Doing this will make the output of your telnet session much more readable. Suggested
terminal types ['terminal emulation' in some clients] are VT100 and VT220, enable ANSI
color if this option is present.
To log in requires three things: hostname, login ID (user name)
and password. Your hostname may be your domain name, or your account's IP address.
IP address is recommended as you will connect slightly faster.
Open a connection to your site. you will be presented with a screen like
this:
Trying 209.3.65.125...
Connected to lsyf/yoa.com.
Escape character is '^]'.
Red Hat Linux release 6.1 (Cartman)
Kernel 2.2.14 on an i686
login: matthew
Password:
You have new mail.
matthew@matthew.lsyf/yoa.com [~]#
This is an example of a successful telnet login. The machine is now ready to
accept commands. Most commands are similar to what some of you may recall from MS-DOS.
dir or ls - List the current files for a given directory
cd - Change directory
pico - A simple text editing program
pine - Launch a telnet based mail program
lynx - Launch a text based web browser
chmod - Modify file permissions
rm - Remove [delete] a file
These are but a few examples of the commands and functions which can be done
through your shell accounts. Please review our POLICIES before attempting
to run any background process's. NOTE: Running irc programs from a shell will
result in termination of your entire account.
